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    <script>
      // 1 7 2 3
      // 宏 [0]
      // 微 [ 8 4 6]

      setTimeout(() => {
          console.log(0)
      }, 0);
      new Promise((resolve,reject)=>{
          console.log(1)
          resolve()
      }).then(()=>{
          console.log(2)
          new Promise((resolve,reject)=>{
              console.log(3)
              resolve()
          }).then(()=>{
              console.log(4)
          }).then(()=>{
              console.log(5)
          })
      }).then(()=>{
          console.log(6)
      })

      new Promise((resolve,reject)=>{
          console.log(7)
          resolve()
      }).then(()=>{
          console.log(8)

          console.log(12)
      })
    </script>
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